Engine



Jan. 7, 1930.

ENGINE Filed March 11. 1926 3 Sheets-Sheet 1 INVENTOR. Ai'ffi unflpcfna' By Wt? lw/ H15 ATTOQINE! A. E. PETERS 1,742,725

Jan. 7, 1930. A. E. PETERS 1,742,725

' ENGINE Filed March 11. 1926 s Sheets-Sheet 2 INVENTOR. HvZ/uazEPefeM BY /W'.

19/15 ATTORNEY.

3 Sheets-Sheet 5 ENGINE INVENTOR fizmEPeze H16 A ORNEI.

A. E. PETERS Filqd March 11. 1926 llll Jan. 7, I930.

Patented Jan. 7, 1930 UNETED, STATES ARTHUR E, PETERS, 01 LITTLETON, COLORADO, ASSIGNOB T IHGEBSOLL-RAND GOM- IEAHY, OF JERSEY CITY, NEW JERSEY, A COR-PCHATIQH 93 NEW ENGINE Application filed, March 11, 1928. Serial No. sep a.

This invention relates to engines and more particularly to fluid actuated engines of the square piston type in which there is provided a rotating piston directly connected to a crank and adapted to reciprocate within a reciprocating frame.

Gne object of the invention is to increase the efficiency of the engine and to reduce clearance.

Another object of the invention is to reduce the lateral and end thrust on the hearing faces due to unbalanced pressures on the pistons. Still another object of' the invention is to eliminate biasingpressures on the -5 throttle valve.

Other objects and advantages will be in part obvious and in part pointed out hereinafter.

The invention will be more clearly understood by reference to the following description and the drawing fiorming part of the specification in which similar reference characters refer to similar. parts, in which Figure l is a plan view, partlyin section,

- of a hoist provided with an engine constructed in accordancewith the practice of the invention, the section being taken alon the line 1 l of Figure 2 looking in the irection of the arrows,

Figure 2 is a cross sectional view of the engine along the line 2 2 of Figure 1 looking in the direction ofthe arrows, and

*igures 3, t and 5 are cliag-rammatical views of the engine showing the pistons at important points in their cycle of operation,

Referring to the drawings, the motor comprises a cylinder A having. a front head B and a heel; head C in which a pair of pistons I) and E are adapted to reciprocate directly connected through anti-friction bearings F to crank pins of a pair of similar crank shafts The crank shafts H are each provided with a gear J of similar size meshing with a main gear K keyed to a drive shaft L. A throttle valve chest 0 is mounted on the outer face of the cylinder head B within which a. throttle valve P is adapted to be reciprocated by means of athrottle control 1ever Q, to regulate the flow of motive fluid to the engine.

The, pistons D and are each adapted to reciprocate in frames and S, respectively, (Figure 2), which are movable sli'dabljy and with relatively little clearance in wearing strips T mounted on opposite end tacos of the cylinder A to prevent leakage of motive fluid. The frames and S are also )rovide d with wearing strips U between which the pistons D and E are adapted to slide, the strips U being adapted to prevent leakage of motive fluid from. one end of the-piston to the other. The type of piston D, and E- provided is substantially as described in copending application of Arthur Peters, Serial No. 68,4- t8, filed November 11, 1925, in which type the pistons D andE; are constantly filled with motive fluid which is adapted to be distributed to the ends of the pistons D and E by means of ports V and W in the side faces of the pistons. The ports V and W are adapted, to cooperate with ports Z in the front cylinder head B to admit the motive fluid. Small ports. 15 are also provided in the pistons and E to maintain pressure within the pistons when the ports V and W are out of registry with the ports Air is admitted tl ir ough ports in the front head B into the pistons D and E by means of ports I) in the front faces of the pistons D and E and the ports and W, for one or another of these ports is at all times in register with the supply port i The, operation of the pistons D and is shown more clearly in Fi ures 3, 4 and Considering first the piston Figure 3 shows this piston just starting its downward power stroke. The port V registers with the groove X in the cylinder head'which permits motive fluid to flow through the groove to the space between the upper face of the piston D and the frame R forcing the piston downwardly. Figure 4 shows 'th e piston at the point of cut-off, the port Vhaving ust passed out of communication with the groove X whereupon motive fluid in the upper chamber is permitted to expand for the remainder of the stroke of the piston D. In Figure 5, the piston D is shown at the end of its-stroke, at which point exhaust of the motive fluid in the upper chamber of the piston D com- I by means of the port WV cooperating with the groove Y in the cylinder head B and the exhaust is controlled as before by the frame R cooperating with grooves e in the cylinder heads B and C and communicating with atmosphere through a passage f.

The operation of the piston E is similar to that of the piston D except that the cranks G are set at one quarter stroke apart so as to produce a more eflicient torque at the drive shaft L. The frames R and S are not actuating pistons in this application of the inin this instance to be used only as cylinders for the pistons D and E and to control the exhaust grooves a and e.

As has been described above, the hollow pistons D and E are always filled with live motive fluid. This has a tendency to pro duce unbalanced pressure in the interior of the piston tending to thrust the pistons D and E against the rear cylinder head C. This is undesirable since the pressure is large enough to cause rapid wear on the hearing faces. By this invention this tendency is counteracted by cutting away a portion of the inner wall of the piston D in the form of a circular orifice g and transferring the pressure to the crank shaft H which is more adapted to receive end thrust pressure due to the fact that this shaft is mounted in bearings 1 located against the wall 8 which are adapted to receive the end thrust. Leakage is prevented through the orifice g by means of a cup leather h reinforced on either side by plates 7' of metal or other stiff material and adapted to bear against the outer race of the ball bearing F and to rotate therewith. These cup leather assemblies are positioned loosely in place and have limited motion since they are confined between the outer race of the ball bearings and the edge of the openings 6. There is substantially no wear on the cup leather h, the only motion between it and the edge of the orifice 9 being endwise and relatively slight.

Preferably the orifice g is of such diameter that the unbalanced pressure on the piston D tends preferably to press the piston D against the front cylinder head B whereby leakage of motive fluid from the ports V, lV and Z is prevented. The elimination of lateral thrust on the pistons D and E materially reduces the friction loss in the motor and increases the durability as well.

The crank shafts H are provided with antifriction bearings q suitably mounted in the back head 0, and also with anti-friction thrust and radial bearings 9" mounted in a flange s which carries an anti-friction bear t for the main drive shaft L. Between the bearings g and 1 there are provided suitable counterbalancing weights to mounted on the shaft H and adapted to counterbalance the weight of the pistons D and E respectively on the crank pins G. The back head C is adapted to house the counterbalancing weights u and the gears J and K and to this end is provided with a rearwardly extending wall 2) having a flange w adapted to be attached by means of suitable bolts :2: to the flange s.

The throttle valve P is arranged to be actuated by a pinion (not shown) operated by the throttle lever q and meshing with a rack 9' attached to an extension 2 of the valve P.

It is preferable that a throttle valve for use in engines be unaffected by the pressure of the motive fluid which it controls, that is, that the pressures on the throttle valve be balanced. To this end the valve chest is provided with a valve bushing 2 provided at intervals with rings of perforations 3 to permit the passage of motive fluid from suitable annular grooves 4, 5, 6 and 7 to the valve P. The valve P is preferably cylindrical and may rotate as well as reciprocate within the bushing 2. Spaced perforations 8, 9, 10 and 11 are provided in the valve P to cooperate with the perforations 3 communicating with the ring grooves 4, 5, 6, and 7 respectively.

The ring grooves 5 and 7 are adapted to conduct motive fluid to ring cuts 12 and 13, respectively, leading to the ports Z in the cylinder head B and thence to the interior of the pistons D and E respectively. The ring groove 4 is connected with a supply pipe 14 from a suitable source. The ring groove 6 is adapted to conduct motive fluid to a clutch mechanism (not shown) for connecting suitable drums to the motor.

Shifting the valve P to the osition shown in Figure 1 associates the per orations in the valve P with the associated ring grooves 4, 5, 6 and 7. In its neutral position, the valve P is out of registry with all of the perfora tions in the bushing 2. The valve is normally held in its neutral position by means of coil springs 15 at opposite ends of the valve P and held in the bore of the valve chest 0 by means of suitable plugs 16. The plugs 16 are provided with escape passages 17 to allow leakage air to pass to atmos here. Moving the valve P to the opposite en of the bushing iii 2 causes the perforations 8, 9, and to communicate with the ring grooves 7, 4 and 5 respectively which supplies air, as before, from the interior of the valve P to the pistons, but allows air under pressure to escape from the ring groove 6 past the end of the Valve to atmosphere through the port 17. In both positions of the valve as above described the motor rotates in the same direction.

The hoist construction, and the clutch mechanism, to be operated by the engine above described, may be substantially as described in copending application of A. E. Peters, Serial No. 41295. filed July 3, 1925. The details of the clutch mechanism are not described here in this application since any convenient form of mechanism for this purpose may be employed. T he clutch mechanism (not shown) may be encased in a casing and is adapted to operate one or the other of a pair of drums 21 and 22 rotatable on a center bearing 23, the center bearing being hollow to accommodate the drive shaft L. The casin 20 is rigidly held in position with H, respect to the engine by a cage 23 attached by means of suitable bolts 24 to the flange w of the cylinder back head C and the casing 20. Suitable apertures are provided in the cage to permit the ropes 25 to pass out to the exterior. The cage 23 is provided, adjacent the flanges of the drums 21 and 22, with beveled edges 26 to lead the rope 25 into the space between the flanges of the drums 21 and 22.

As shown in Figure 2, the cage 23 is integrally formed with a foot or base 27 by means of which the hoist may be mounted on a suitable support.

The exhaust passages 0. e and f may lead to a suitable discharge pipe connections 28 to direct the exhaust most conveniently.

Thus by the above construction are accomi lisl ed among others the objects hereinbefore referred to.

I claim:

1. An engine comprising a cylinder, front and back heads for said cylinder, a plurality of reciprocating frames in said cylinder, a rotary piston within each of said frames, hollow to receive motive fluid under full pressure for actuating the pistons. a crank shaft for ea h of said pistons directly connected to said pistons. means to reduce the lateral thrust due to the pressure of the motive fluid against the faces of said pistons, including a disk ino *able relatively to each of said pistons and arranged to transmit the thrust of such air pressure to the crank shaft.

2. An engine comprising a cylinder, front and back heads for said cylinder, reciprocating frames within said cylinder between said back heads, rotary piston in each of said frames, a crank shaft directly connected to each of said rotary pistons and journaled in said back head, a main drive shaft geared to each of said crank shafts, ports in the front faces of said rotary pistons to receive motive fluid into the interior of the pistons, an aperture in the rear face of the piston to balance the front and rear pressure area of the piston and means within the piston to prevent leakage through said aperture.

3. An engine comprising a cylinder, front and back heads for said cylinder. reciprocating frames within. said cylinder between said heads, a rotary piston in each of said frames, a crank shaft directly connected to each of said rotary pistons and journaled in said back head, a main drive shaft geared to each of said crank shafts, ports in the front faces of said rotary pistons to receive motive fluid into the interior of the pistons, apertures in the rear faces of the pistons to balance the front and rear pressure areas of the pistons and means within the pistons to prevent leakage through said apertures including a tight disk within each of said pistons and movable with respect thereto adapted to be pressed against the crank shaft associated with each piston.

4-. An engine comprising a cylinder, front and back heads for said cylinder, a frame reci 'nocable within said cylinder between said heads, a crank shaft extending into the cylinder, a rotary piston within said frame and connected to the crank of said shaft, a ported face on said piston adapted to receive motive fluid constantly into said piston, and means to reduce the lateral thrust of said motive fluid pressure, including a tight disk in said piston bearing against said crank shaft and movable with respect to said piston.

In testimony whereof I have signed this specification.

ARTHUR E. PETERS. 

